Temporal structure/function variation in cultured differentiated human nasal epithelium associated with acute single exposure to tobacco smoke or E-cigarette vapor.

AbstractObjective: Mucociliary clearancesustains a baseline functionality and an “on demand” capability to upregulate clearance upon irritant exposureinvolving mucus hypersecretion and accelerated ciliary beat frequency (CBF) modulated by nitric oxide (NO). This study characterized these elements as well as cellular and exogenous NO concentrations subsequent to a single exposureto tobacco smoke(TS) or e-cigarette vapor (EV) on cultured human airway epithelium.Materials and methods: Air–liquid interface (ALI) airway epithelial cultures per nonsmoking human subjects were subjected to single TS or EV exposures. Measures of ciliary function and secretion were performed and cellular and exogenous NO concentrations under control and experimental conditions were assessed.Results: Both TS and EV exposuresresulted similar patterns of decline in CBF within 1 min of the completion of exposurefollowed by a gradual return often exceeding baseline within 1 h. Post- exposureexamination of exposed cultures suggeste...